If you've ever stood at the pump wondering whether diesel or petrol is more cost-effective, you're not alone. With fuel prices continuing to fluctuate and new environmental regulations entering the scene, knowing which option truly offers better value can be confusing. So, is diesel cheaper than petrol right now — and more importantly, is it still the smarter choice in the long run?
In this post, we’ll unpack the current fuel pricing landscape, compare efficiency and running costs, and give you the real-world facts to help you make a more informed decision for your Small business.
Let’s start with the fundamental question: is petrol more expensive than diesel? Historically, diesel used to be cheaper than petrol per litre. However, things have changed over the years, especially in the UK.
The short answer? It depends on your driving habits. Here's a quick look:
| Factor | Diesel | Petrol |
|---|---|---|
| Price per litre (UK average) | £1.54 | £1.46 |
| Fuel efficiency (miles per gallon) | 55–65 MPG | 40–50 MPG |
| Maintenance costs | Higher | Lower |
| Emissions cost (ULEZ/tax) | Higher | Lower |
While diesel may cost more per litre, its greater fuel economy can offset that — but only if you cover enough mileage annually to make the difference worthwhile.
Diesel is generally more expensive than petrol per litre in the UK, but diesel engines are more fuel-efficient. For high-mileage drivers, diesel can still work out cheaper overall, while low-mileage users may find petrol the more economical option.
As of mid-2025, petrol is still slightly cheaper than diesel in terms of price per litre across most UK filling stations. But it's essential not to just compare prices at the pump. Consider the overall cost of running the car, including:
For example, diesel cars are usually fitted with particulate filters, which can be expensive to repair or replace. Petrol engines tend to have lower maintenance costs and are generally more suitable for urban, short-distance driving.
Diesel may still be the better bet. Despite higher fuel prices, greater efficiency means you’ll fill up less often. You could save over £300 per year if you do more than 15,000 miles annually.
Petrol is typically more cost-effective for city driving. Diesel engines can suffer in stop-start traffic and take longer to warm up, making them less efficient on short trips.
Government policies have made diesel cars less attractive in recent years:
This means the total cost of owning a diesel vehicle could end up higher unless you’re making the most of the efficiency over long distances.
So, is diesel cheaper than petrol overall? If you're clocking up thousands of motorway miles a year, diesel still makes sense from a cost-per-mile perspective. But for many drivers—especially those in urban areas—petrol may be the better long-term investment.
Always factor in your lifestyle, driving habits, and local fuel prices. With the UK moving towards greener alternatives and EV adoption rising, both petrol and diesel could be short-term solutions in a longer transition for all the small households and small businesses.
If you're buying your next vehicle, think beyond just the fuel price. Look at fuel economy, maintenance, taxes, and resale value to calculate the true cost of ownership.
Need help understanding vehicle running costs or choosing the right car? Stay tuned to our blog for regular comparisons, expert insights, and updates on fuel and vehicle trends.
